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tetra

[te-truh]
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noun

any of several tropical, freshwater fishes of the family Characidae, often kept in aquariums.

Origin of tetra

1930–35; shortening of New Latin Tetragonopterus former genus name. See tetragon, -o-, -pterous

tetra-

a combining form meaning “four,” used in the formation of compound words: tetrabranchiate.
Also especially before a vowel, tetr-.

Origin of tetra-

< Greek, combining form of téttara, neuter of téttares four
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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British Dictionary definitions for tetra

tetra

noun plural -ra or -ras

any of various brightly coloured tropical freshwater fishes of the genus Hemigrammus and related genera: family Characidae (characins)

Word Origin for tetra

C20: short for New Latin tetragonopterus (former genus name), from tetragon + -o- + -pterous, from Greek pteron wing

tetra-

before a vowel tetr-

combining form

fourtetrameter

Word Origin for tetra-

from Greek
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for tetra

tetra-

word-forming element meaning "four," from Greek tetra-, combining form of tettares, tessares "four" (see four).

Online Etymology Dictionary, © 2010 Douglas Harper
tetra in Medicine

tetra-

pref.

Four:tetradactyl.
Composed of or containing four atoms, molecules, or groups:tetrasaccharide.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.